- Research article
- Open access
- Published:
Dissecting the signaling pathways associated with the oncogenic activity of MLK3 P252H mutation
BMC Cancer volume 14, Article number: 182 (2014)
Abstract
Background
MLK3 gene mutations were described to occur in about 20% of microsatellite unstable gastrointestinal cancers and to harbor oncogenic activity. In particular, mutation P252H, located in the kinase domain, was found to have a strong transforming potential, and to promote the growth of highly invasive tumors when subcutaneously injected in nude mice. Nevertheless, the molecular mechanism underlying the oncogenic activity of P252H mutant remained elusive.
Methods
In this work, we performed Illumina Whole Genome arrays on three biological replicas of human HEK293 cells stably transfected with the wild-type MLK3, the P252H mutation and with the empty vector (Mock) in order to identify the putative signaling pathways associated with P252H mutation.
Results
Our microarray results showed that mutant MLK3 deregulates several important colorectal cancer- associated signaling pathways such as WNT, MAPK, NOTCH, TGF-beta and p53, helping to narrow down the number of potential MLK3 targets responsible for its oncogenic effects. A more detailed analysis of the alterations affecting the WNT signaling pathway revealed a down-regulation of molecules involved in the canonical pathway, such as DVL2, LEF1, CCND1 and c-Myc, and an up-regulation of DKK, a well-known negative regulator of canonical WNT signaling, in MLK3 mutant cells. Additionally, FZD6 and FZD10 genes, known to act as negative regulators of the canonical WNT signaling cascade and as positive regulators of the planar cell polarity (PCP) pathway, a non-canonic WNT pathway, were found to be up-regulated in P252H cells.
Conclusion
The results provide an overall view of the expression profile associated with mutant MLK3, and they support the functional role of mutant MLK3 by showing a deregulation of several signaling pathways known to play important roles in the development and progression of colorectal cancer. The results also suggest that mutant MLK3 may be a novel modulator of WNT signaling, and pinpoint the activation of PCP pathway as a possible mechanism underlying the invasive potential of MLK3 mutant cells.
Background
Mixed-lineage kinase 3 (MLK3) belongs to a family of seven different mammalian MLKs, that are clustered in three subgroups accordingly with their structural similarities: the MLKs (MLK1, MLK2, MLK3, MLK4); the dual-leucine-zipper-bearing kinases (Dlk and Lzk); and zipper sterile-α-motif kinase (Zakα and Zakβ) [1].
MLK3 protein is composed by a Src-homology-3 (SH3) domain, located at the amino terminus of the protein, followed by a kinase domain, a leucine-zipper region, a Cdc42/RAC interacting binding motif (CRIB) and a Proline/Serine/Threonine-rich (P/S/T-rich) carboxy terminal domain [1–4]. All these domains show a very high degree of homology between MLK members (MLK1-MLK4) [1], except the carboxy-terminus P/S/T- rich domain which is the less conserved region among MLK proteins [1].
MLK3 is a serine/threonine protein kinase that regulates the mitogen-activated protein kinase (MAPK) pathway, activating ERK, p38 and JNK in response to extracellular signals [1, 5]. Additionally, functional studies have demonstrated that overexpression of wild-type MLK3 leads to morphological transformation of NIH 3T3 fibroblasts and growth in soft agar, a capacity that is MEK/ERK dependent [6]. Further, MLK3 has been demonstrated to function as a scaffolding protein, involved in the formation of a multiprotein complex containing MLK3/BRAF/RAF1 [1, 5, 7, 8]. The formation of this complex was shown to be important for the activation of wild-type BRAF and, consequently, to the activation of ERK signaling [1, 5, 7, 8]. Furthermore, MLK3 was reported to be important for the proliferation of tumor cells, bearing either oncogenic KRAS or neurofibromatosis-1 (NF1) or NF2 inactivating mutations [8]. In addition, the MLK3 signaling activation was associated with an increase in the migratory and invasive capacity of tumor cells in gastric [9], breast [10–12], lung [13] and ovarian [14] cancers. All together, these observations implicate MLK3 as a cancer-related gene although, until recently, nothing was known about MLK3 gene deregulation in primary cancer tissues.
Our group reported the occurrence of MLK3 mutations in microsatellite unstable (MSI) gastrointestinal tumors (both sporadic and hereditary forms) in a frequency of about 20%. Using in vitro transforming assays, we demonstrated that several MLK3 mutations affecting different domains of the protein had transforming potential when compared to cells expressing the wild-type and the kinase-dead forms of the protein [15]. These results were further supported by in vivo studies in which one of the two most transforming mutations (P252H – located in the kinase domain) was found to be tumorigenic and to give rise to highly invasive tumors when subcutaneously injected in nude mice. Thus, our previous work pointed mutant MLK3 as a new oncogene in MSI gastrointestinal cancers, however, the signaling pathways associated to its oncogenic activity remained to be explored.
In this work, we aimed at identifying the signaling pathways associated to mutant MLK3, in particular the P252H mutation. The reasons underlying the choice for this mutation were: (a) it was one of the most transforming mutations previously analyzed; (b) showed high tumorigenic capacity with strong invasive potential in in vivo studies; and (c) it was located in the kinase domain which is an important domain for the regulation of downstream signaling pathways.
The results showed that P252H mutation interferes with important colorectal cancer-associated signaling pathways such as WNT, MAPK, NOTCH, TGF-β and P53.
Methods
cDNA constructs and mutagenesis
Wild-type MLK3 and mutant sequences were cloned into pLENTID6/V5 directional TOPO (Invitrogen). Mutant MLK3 P252H sequence was generated by site-directed mutagenesis using the MLK3 wild-type sequence cloned in pLENTID6/V5 as template. pLENTID6/V5 empty vector (Mock) was obtained by the insertion of a small fragment of cDNA in order to circularize the plasmid.
Cell lines
Human HEK293 were maintained in DMEM (Gibco, Invitrogen) supplemented with 10% FBS and 1% penicillin–streptomycin (Gibco, Invitrogen), and were incubated in a humidified chamber with 5% CO2 at 37°C.
Transfections
For HEK293 stable transfections, ViraPower Lentiviral Expression kit (Invitrogen) was used for the transduction of the MLK3 wild-type and mutant P252H sequences as well as the empty vector. Lentiviral transduction was performed following the manufacturer’s instructions. Transduced cells were selected by antibiotic resistance (blasticidin, 12 μg/ml) (Gibco, Invitrogen). The expression levels of MLK3 in the different clones selected were measured by western-blot.
RNA extraction and cDNA synthesis
Total RNA was isolated from cell lines using TriPure Isolation Reagent (Roche Applied Science), following manufacturer’s instructions. Complementary DNA was synthesized from 1 μg of total RNA using SuperScriptII Reverse Transcriptase (Invitrogen) and Random Primers (Invitrogen).
Labeling and hybridization
Five hundred ng aliquots of RNA from the samples were quality checked using the Agilent 2100 Byoanalyzer and only samples above integrity quality number (RIN) 8 [16] were used and amplified according to the specifications of the Illumina® TotalPrep™ RNA Amplification Kit (Ambion, Austin, TX, USA). The cRNA samples were applied to the arrays of Sentrix® Human-v6 Expression BeadChip (Illumina, San Diego, CA, USA) and hybridized according to manufacturer's specifications. The Sentrix BeadChips were scanned with the Illumina's Beadarray system 500G Scanner (Illumina®).
Microarray data analysis
The signal intensity was extracted from the hybridization images, background subtracted and normalized using Illumina Inc. BeadStudio software version 3.3.7. The data produced was checked against the Illumina internal quality controls and loaded into the Bioconductor software [17, 18]. To identify differentially expressed genes based on a moderate t-test, the bioconductor Limma package [19] was used. Genes were selected based on a p-value cut-off (after adjustment) of p < 0.01 to control the false discovery rate (FDR) [20]. To test the association of selected differentially expressed genes with KEGG pathways [21], information provided in the Illumina annotation files (Sentrix® Human-v6 Expression BeadChip) Hypergeometric test available in the GOstats packages [22] was used. A p-value cut off of 0.05 was considered. Microarray data can be found at the GEO repository with the accession number GSE54611.
Real-time PCR
One μl of cDNA was added to 10 μl Real-Time PCR mixtures containing 1x TaqMan® Universal PCR Master Mix, No AmpErase® UNG (Applied Biosystems) and 1x TaqMan® MGB specific probes and primers mix. Taqman expression assays for BMP6 (Hs01099594_m1), CCND1 (Hs00277039_m1), FZD10 (Hs00273077_s1), LEF1 (Hs00212390_m1) were purchased from Applied Biosystems. The eukaryotic 18S rRNA assay (Hs99999901_s1; Applied Biosystems) was used as an endogenous control gene. Standard TaqMan thermocycling conditions were used: 1 cycle of 2 minutes at 50°C, 1 cycle of 10 minutes at 95°C, 40 cycles of 15 seconds at 95°C followed by 1 minute at 60°C in an ABI Prism 7000 (Applied Biosystyems). Real-Time PCR assays (absolute quantification) were performed in, at least, three biological replicas.
Statistical analyses
For statistical analyzes of in vitro transformation assays a t-student test was used and p < 0.05 was taken as statistically significant. Specific statistical tests used for microarray interpretation are embedded in the corresponding materials and methods section.
Results and discussion
MLK3 P252H mutation affects fundamental colorectal cancer-associated pathways
In order to assess the effect of a tumorigenic MLK3 mutant on a genome-wide level, we performed microarray-based expression profiling experiments. We used Illumina Whole Genome arrays on three biological replicas of human HEK293 cells stably transfected with the wild-type MLK3, with the MLK3 P252H mutation and with the empty vector (Mock). The expression profiles were obtained by comparing all biological replicas from each transfection experiment. Colorectal cancer cell lines were not used in this experiment, as proteins from the MAPK pathway are frequent mutation targets in this type of cancer, and would most likely interfere with the interpretation of the results. The expression profiles were compared to identify genes that were differentially expressed at least 2 log-fold (FDR < 0.01) between wild-type and Mock, as well as between P252H and Mock. A final set of 445 genes was identified which showed significant differential expression only between P252H and wild-type and not between wild-type and Mock (Figure 1a). The most statistically significantly differentially expressed genes are displayed in Figure 1b. The genes identified were significantly enriched (p < 0.05) in several KEGG pathways (Table 1) involved in overall biosynthesis processes, as well as in response in disease relevant processes. Interestingly, the colorectal pathway, which encompasses several relevant pathways such as WNT, MAPK, NOTCH, TGF-β and P53, was significantly over-represented (Figure 1c). These signaling pathways are crucial to maintain intestinal epithelium homeostasis by balancing the rate of proliferation, apoptosis, and differentiation along the crypt-villus axis, and their de-regulation is commonly associated to colorectal cancer initiation and progression [23]. Corroborating our results, a recent study using both in vivo and in vitro approaches showed that MLK3 signaling is important in intestinal mucosal healing and epithelial cell motility [24], therefore implicating MLK3 signaling in the maintenance of intestinal epithelial homeostasis.
In order to further validate the microarray data, a set of differentially expressed genes (LEF1, CCND1, FZD10, and BMP6) were selected for validation by real-time PCR in HEK293 cells stably expressing MLK3 wild-type or MLK3 P252H. The results obtained with the microarrays were validated for all genes tested (Figure 1d).
Of particular interest are the alterations that mutant MLK3 induces in the WNT pathway. Activation of canonical WNT signaling through WNT/β-catenin cascade has traditionally been regarded as a critical player in colorectal tumorigenesis [25]. More recently, accumulating evidence supports a role for the non-canonical WNT planar cell polarity (PCP) pathway, a signaling cascade involved in the polarization of cells during tissue remodeling, and cell adhesion and motility, in cancer progression, invasion, metastasis, and angiogenesis [26–28]. A more detailed analyzes of our microarray data showed that the expression of several molecular components of the canonical pathway, such as DVL2, LEF1, CCND1 and c-MYC were down-regulated in MLK3 mutant cells, and the expression of DKK, a well-known negative regulator of canonical WNT signaling [29], was up-regulated (Figure 1c and d). On the other hand, genes encoding two WNT receptors known to act as negative regulators of the canonical WNT/β-catenin signaling cascade and as positive regulators of the PCP pathway, FZD6 and FZD10, were found to be up-regulated in P252H cells (Figure 1c and d). Taken together, the down-regulation of DVL2, LEF1, CCND1 and c-MYC, and the up-regulation of DKK and FZD receptors suggest a role of mutant MLK3 as a molecular switch between canonic and non-canonic WNT signaling. In accordance, it was recently reported that MLK3 reduces the expression of β-catenin/TCF downstream targets by promoting the interaction between β-catenin and KLF4, a known repressor of β-catenin/TCF transcriptional activity [30]. Furthermore, in accordance with a role of PCP in colorectal cancer, FZD10 was recently demonstrated to be up-regulated in colorectal cancers and matched liver metastases, and its over-expression was associated with the activation of non-canonical WNT pathway [31, 32].
Conclusion
In conclusion, our results provide an overall view of the expression profile associated with mutant MLK3, and they support the functional role of mutant MLK3 by showing a deregulation of several signaling pathways known to play important roles in the development and progression of colorectal cancer. The results also suggest that mutant MLK3 may be a novel modulator of WNT signaling, and pinpoint the activation of the PCP pathway as a possible mechanism underlying the invasive potential of MLK3 mutant cells. Nevertheless, further studies are required in order to validate this hypothesis in a panel of gastrointestinal cell lines and human primary tumors, to determine if the altered signaling pathways are common to other MLK3 mutations, and to investigate the role of mutant MLK3 in the context of mutant KRAS and BRAF genes.
Abbreviations
- MLK:
-
Mixed lineage kinase
- WNT:
-
Wingless type
- BMP:
-
Bone morphogenetic protein
- TGF-β:
-
Transforming growth factor β
- MSI:
-
Microsatellite instability
- PCP:
-
Planar cell polarity
- DKK:
-
Dickkopf
- FZD:
-
Frizelled
- DVL2:
-
Dishevelled
- LEF1:
-
Lymphoid enhancer binding factor 1
- CCND1:
-
Cyclin D1
- KLF4:
-
Krupfel-like factor
- c-MYC:
-
v-myc avian myelocytomatosis viral oncogene homolog
- TCF:
-
T cell-specific transcription factor
- PCR:
-
Polymerase chain reaction
- MEK:
-
MAP kinase-ERK kinase
- ERK:
-
Extracellular signal-regulated kinase
- MAPK:
-
Mitogen-activated protein kinase
- JNK:
-
c-Jun amino-terminal kinase
- BRAF:
-
v-raf murine sarcoma viral oncogene homolog B
- KRAS:
-
Kirsten rat sarcoma viral oncogene homolog
- Dlk:
-
Dual-leucine-zipper-bearing kinase
- Lzk:
-
Leucine-zipper-bearing kinase
- Zak:
-
Zipper sterile-α-motif kinase
- SH3:
-
Src-homology-3.
References
Gallo KA, Johnson GL: Mixed-lineage kinase control of JNK and p38 MAPK pathways. Nat Rev Mol Cell Biol. 2002, 3 (9): 663-672. 10.1038/nrm906.
Burbelo PD, Drechsel D, Hall A: A conserved binding motif defines numerous candidate target proteins for both Cdc42 and Rac GTPases. J Biol Chem. 1995, 270 (49): 29071-29074. 10.1074/jbc.270.49.29071.
Gallo KA, Mark MR, Scadden DT, Wang Z, Gu Q, Godowski PJ: Identification and characterization of SPRK, a novel src-homology 3 domain-containing proline-rich kinase with serine/threonine kinase activity. J Biol Chem. 1994, 269 (21): 15092-15100.
Ing Y, Leung I, Heng H, Tsui L, Lassam N: MLK-3: identification of a widely-expressed protein kinase bearing an SH3 domain and a leucine zipper-basic region domain. Oncogene. 1994, 9 (6): 1745-1750.
Chadee D, Kyriakis J: A novel role for mixed lineage kinase 3 (MLK3) in B-Raf activation and cell proliferation. Cell Cycle. 2004, 3 (10): 1227-1229. 10.4161/cc.3.10.1187.
Hartkamp J, Troppmair J, Rapp UR: The JNK/SAPK activator mixed lineage kinase 3 (MLK3) transforms NIH 3T3 cells in a MEK-dependent fashion. Cancer Res. 1999, 59 (9): 2195-2202.
Chadee DN, Kyriakis JM: MLK3 is required for mitogen activation of B-Raf, ERK and cell proliferation. Nat Cell Biol. 2004, 6 (8): 770-776. 10.1038/ncb1152.
Chadee DN, Xu D, Hung G, Andalibi A, Lim DJ, Luo Z, Gutmann DH, Kyriakis JM: Mixed-lineage kinase 3 regulates B-Raf through maintenance of the B-Raf/Raf-1 complex and inhibition by the NF2 tumor suppressor protein. Proc Natl Acad Sci U S A. 2006, 103 (12): 4463-4468. 10.1073/pnas.0510651103.
Mishra P, Senthivinayagam S, Rangasamy V, Sondarva G, Rana B: Mixed lineage kinase-3/JNK1 axis promotes migration of human gastric cancer cells following gastrin stimulation. Mol Endocrinol. 2010, 24 (3): 598-607. 10.1210/me.2009-0387.
Chen J, Gallo KA: MLK3 regulates paxillin phosphorylation in chemokine-mediated breast cancer cell migration and invasion to drive metastasis. Cancer Res. 2012, 72 (16): 4130-4140. 10.1158/0008-5472.CAN-12-0655.
Chen J, Miller EM, Gallo KA: MLK3 is critical for breast cancer cell migration and promotes a malignant phenotype in mammary epithelial cells. Oncogene. 2010, 29 (31): 4399-4411. 10.1038/onc.2010.198.
Cronan MR, Nakamura K, Johnson NL, Granger DA, Cuevas BD, Wang JG, Mackman N, Scott JE, Dohlman HG, Johnson GL: Defining MAP3 kinases required for MDA-MB-231 cell tumor growth and metastasis. Oncogene. 2012, 31 (34): 3889-3900. 10.1038/onc.2011.544.
Chien ST, Lin SS, Wang CK, Lee YB, Chen KS, Fong Y, Shih YW: Acacetin inhibits the invasion and migration of human non-small cell lung cancer A549 cells by suppressing the p38alpha MAPK signaling pathway. Mol Cell Biochem. 2011, 350 (1–2): 135-148.
Zhan Y, Abi Saab WF, Modi N, Stewart AM, Liu J, Chadee DN: Mixed lineage kinase 3 is required for matrix metalloproteinase expression and invasion in ovarian cancer cells. Exp Cell Res. 2012, 318 (14): 1641-1648. 10.1016/j.yexcr.2012.05.002.
Velho S, Oliveira C, Paredes J, Sousa S, Leite M, Matos P, Milanezi F, Ribeiro AS, Mendes N, Licastro D, Karhu A, Oliveira MJ, Ligtenberg M, Hamelin R, Carneiro F, Lindblom A, Peltomaki P, Castedo S, Schwartz S, Jordan P, Aaltonen LA, Hofstra RM, Suriano G, Stupka E, Fialho AM, Seruca R: Mixed lineage kinase 3 gene mutations in mismatch repair deficient gastrointestinal tumours. Hum Mol Genet. 2010, 19 (4): 697-706. 10.1093/hmg/ddp536.
Schroeder A, Mueller O, Stocker S, Salowsky R, Leiber M, Gassmann M, Lightfoot S, Menzel W, Granzow M, Ragg T: The RIN: an RNA integrity number for assigning integrity values to RNA measurements. BMC Mol Biol. 2006, 7 (1): 3-10.1186/1471-2199-7-3.
Gentleman R, Carey V, Bates D, Bolstad B, Dettling M, Dudoit S, Ellis B, Gautier L, Ge Y, Gentry J, Hornik K, Hothorn T, Huber W, Iacus S, Irizarry R, Leisch F, Li C, Maechler M, Rossini A, Sawitzki G, Smith C, Smyth G, Tierney L, Yang J, Zhang J: Bioconductor: open software development for computational biology and bioinformatics. Genome Biol. 2004, 5 (10): R80-10.1186/gb-2004-5-10-r80.
R Development Core Team: R: A language and environment for statistical computing. 2008, Vienna, Austria: R Foundation for Statistical Computing
Smyth G: Limma: linear models for microarray data. 2005, New York: Springer
Benjamini Y, Hochberg Y: Controlling the false discovery rate: a practical and powerful approach to multiple testing. J R Stat Soc B. 1995, 57: 289-300.
Liu T, Lin C, Falcon S, Zhang J, MacDonald J: Kegg: a data package containing annotation data for KEGG. R package version 2.2.0. 2007
Gentleman R, Falcon S: Gostats: tools for manipulating GO and microarrays. R package version 2.6.0. 2007
Radtke F, Clevers H, Riccio O: From gut homeostasis to cancer. Curr Mol Med. 2006, 6 (3): 275-289. 10.2174/156652406776894527.
Kovalenko PL, Kunovska L, Chen J, Gallo KA, Basson MD: Loss of MLK3 signaling impedes ulcer healing by modulating MAPK signaling in mouse intestinal mucosa. Am J Physiol Gastrointest Liver Physiol. 2012, 303 (8): G951-G960. 10.1152/ajpgi.00158.2012.
de Lau W, Barker N, Clevers H: WNT signaling in the normal intestine and colorectal cancer. Front Biosci. 2007, 12: 471-491. 10.2741/2076.
Naz G, Pasternack SM, Perrin C, Mattheisen M, Refke M, Khan S, Gul A, Simons M, Ahmad W, Betz RC: FZD6 encoding the Wnt receptor frizzled 6 is mutated in autosomal-recessive nail dysplasia. Br J Dermatol. 2012, 166 (5): 1088-1094. 10.1111/j.1365-2133.2011.10800.x.
Seifert JR, Mlodzik M: Frizzled/PCP signalling: a conserved mechanism regulating cell polarity and directed motility. Nat Rev Genet. 2007, 8 (2): 126-138.
Wang Y: Wnt/Planar cell polarity signaling: a new paradigm for cancer therapy. Mol Cancer Therap. 2009, 8 (8): 2103-2109. 10.1158/1535-7163.MCT-09-0282.
Rao TP, Kuhl M: An updated overview on Wnt signaling pathways: a prelude for more. Circ Res. 2010, 106 (12): 1798-1806. 10.1161/CIRCRESAHA.110.219840.
Thylur RP, Senthivinayagam S, Campbell EM, Rangasamy V, Thorenoor N, Sondarva G, Mehrotra S, Mishra P, Zook E, Le PT, Rana B: Mixed lineage kinase 3 modulates beta-catenin signaling in cancer cells. J Biol Chem. 2011, 286 (43): 37470-37482. 10.1074/jbc.M111.298943.
Fukukawa C, Nagayama S, Tsunoda T, Toguchida J, Nakamura Y, Katagiri T: Activation of the non-canonical Dvl-Rac1-JNK pathway by Frizzled homologue 10 in human synovial sarcoma. Oncogene. 2009, 28 (8): 1110-1120. 10.1038/onc.2008.467.
Nagayama S, Yamada E, Kohno Y, Aoyama T, Fukukawa C, Kubo H, Watanabe G, Katagiri T, Nakamura Y, Sakai Y, Toguchida J: Inverse correlation of the up-regulation of FZD10 expression and the activation of beta-catenin in synchronous colorectal tumors. Cancer Sci. 2009, 100 (3): 405-412. 10.1111/j.1349-7006.2008.01052.x.
Pre-publication history
The pre-publication history for this paper can be accessed here:http://www.biomedcentral.com/1471-2407/14/182/prepub
Acknowledgements
This work was supported by Grants from The Portuguese Foundation for Science and Technology (FCT) (Project PTDC/SAU-OBD/68310/2006), the Portuguese Ministry for Science and Education, by FEDER- European Fund for the Regional Development and the Programs COMPETE- Programa Operacional de Fatores de Competitividade (POFC) and PEst-C/SAU/LA0002/2013. MJ Oliveira was supported by a Investigator FCT Grant and SV by a Post-doctoral fellowship (SFRH/BPD/69089/2010) from the Portuguese Foundation for Science and Technology (FCT).
Author information
Authors and Affiliations
Corresponding author
Additional information
Competing interests
The authors declare that they have no competing interests.
Authors’ contributions
SV contributed to the acquisition, analysis and interpretation of data and drafted the manuscript; AP participated in the acquisition, analysis and interpretation of data; DL contributed to the acquisition, analysis and interpretation of data; MJO was responsible for the conception and design of the experimental system and critically reviewed the manuscript; FS was involved in the acquisition, analysis and interpretation of data; ES contributed for the conception and design of the experimental system and critically reviewed the manuscript; RS contributed to the conception and design of the project and experimental system, interpretation of data, and was responsible for the final approval of the version to be published.
Authors’ original submitted files for images
Below are the links to the authors’ original submitted files for images.
Rights and permissions
Open Access This article is published under license to BioMed Central Ltd. This is an Open Access article is distributed under the terms of the Creative Commons Attribution License ( https://creativecommons.org/licenses/by/2.0 ), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly credited. The Creative Commons Public Domain Dedication waiver ( https://creativecommons.org/publicdomain/zero/1.0/ ) applies to the data made available in this article, unless otherwise stated.
About this article
Cite this article
Velho, S., Pinto, A., Licastro, D. et al. Dissecting the signaling pathways associated with the oncogenic activity of MLK3 P252H mutation. BMC Cancer 14, 182 (2014). https://doi.org/10.1186/1471-2407-14-182
Received:
Accepted:
Published:
DOI: https://doi.org/10.1186/1471-2407-14-182